1. Field of the Invention
This invention relates generally to imaging systems. More specifically, the present invention is directed to systems and methods of image processing in which rendered images are encoded at a server location and transmitted to a client location to enable real time interactions.
2. Background Discussion
Medical imaging techniques provide doctors and medical technicians with valuable data for patient diagnosis and care. Various imaging techniques include cardiac angiography, peripheral angiography, radiography, computed tomography and positron emission tomography. All of these imaging techniques produce medical images that are studied by medical personnel. A higher quality image leads to more accurate diagnosis.
Radiography is the use of certain spectra of electromagnetic radiation, usually x-rays, to image a human body. Angiography, a particular radiographic method, is the study of blood vessels using x-rays. An angiogram uses a radiopaque substance, or contrast medium, to make the blood vessels visible under x-ray. Angiography is used to detect abnormalities, including narrowing (stenosis) or blockages (occlusions), in the blood vessels throughout the circulatory system and in certain organs.
Cardiac angiography, also known as coronary angiography, is a type of angiographic procedure in which the contrast medium is injected into one of the arteries of the heart, in order to view blood flow through the heart, and to detect obstruction in the coronary arteries, which can lead to a heart attack.
Peripheral angiography, in contrast, is an examination of the peripheral arteries in the body; that is, arteries other than the coronary arteries. The peripheral arteries typically supply blood to the brain, the kidneys, and the legs. Peripheral angiograms are most often performed in order to examine the arteries which supply blood to the head and neck, or the abdomen and legs.
Computed Tomography (CT), originally known as computed axial tomography (CAT or CT scan), is an imaging technique that uses digital geometry processing to generate a three dimensional image of internal features of an object from a series of two-dimensional x-ray images taken around a single axis of rotation. An iodine dye, or other contrast material, may be used to make structures and organs easier to see on the CT picture. The dye may be used to check blood flow, find tumors, and examine other problems.
Positron emission tomography (PET) imaging may also be used. In PET imaging, a short-lived radioactive tracer isotope, which decays by emitting a positron, and which has been chemically incorporated into a metabolically active molecule, is injected into the patient. The radioactive decay of the positrons is measured to generate an image.
In many medical imaging techniques, such as those described above, three-dimensional (3D) volumetric data is used to render a two-dimensional (2D) representation, or image of the 3D data. For example, in a client-server visualization environment, a user may use a client machine, coupled to the server, to interactively visualize 3D data. Multiple users may each use a different client machine, or terminal having particular operational functionality and capabilities. Indeed, volume rendering of 3D data usually requires intensive computations, while the client machines, operatively coupled to the server, may be of different types, such as simple terminal, thin client, or rich client.
The resource limitations, or capabilities of the client machine, are usually an issue since the server typically renders the images and transmits the rendered images to the client. In order for the server and the client machine to have real-time interactions, the server must have sufficient speed for both rendering the 3D dataset and transmitting rendered 2D images to the client machine.
However, for many applications, conventional image processing techniques are not sufficient since the client terminals lack adequate speed and processing capabilities to effectively interact with the server in real-time.
Therefore, it would be an advancement in the state of the art to provide a system and method of generating high quality image data while using thin client terminals in a network.